(1) Field of the Invention
The present invention relates to a head and neck support device for use by persons with a neck dysfunction. Neck dysfunction may result from congenital or acquired disease, trauma, or fatigue. In particular, the present invention relates to a medical restraining device which maintains a desired head position and which decreases neck loads by coupling the head and the torso. The device is comprised of a mast support that is secured to the upper torso and a mast member that extends upwards from the mast support to a position behind the neck and head of the user. One embodiment of the mast support is comprised of a yoke that is worn over the shoulders and the upper torso including the sternum. The mast is preferably attached by a tethering system to a harness as a head grasping apparatus that is worn circumferentially around the head. The head harness includes a forehead strap, a crown or top strap and a nape strap that extends over the nape of the neck. The head harness facilitates grasping the head so that supportive forces may be applied to the head through the tethers, connected between the head harness and the mast. The tethering system also partially transfers the weight of the head, held in the head harness, to the mast mounted on the mast support. That way, the head is supported on the torso, which helps to decrease neck loads, and the head is held to regulate anterior, posterior and sidewards head motion. The mast support is held to the body by a system of straps or by a wheelchair harness if the user is confined to a wheelchair. For cosmetic reasons, the mast support can be worn underneath clothing and a wig or hat can be worn to hide the head harness.
(2) Prior Art
Many persons suffer from neck dysfunction due to the effects of cervical spine trauma, diseases such as cerebral palsy, multiple sclerosis, and muscular dystrophy, or fatigue induced by environmental stress. The result of neck dysfunction is poor head control. The prior art has described various types of devices that relieve neck loads by supporting a person's head on their torso through the use of head rests, under chin supports, or various restraint devices which function by supporting the head and the torso with a rigid structure, connected to a seat in which the person is sitting. Head rests control rearward head motions, but do little to control forward and side motions of the head. Head support from below the jaw line does nothing to control rearward head motion while possibly creating difficulties in swallowing, breathing and sanitation. Devices which attempt to fix torso and head positions relative to a seating device fail because total body immobilization is impossible to achieve; inevitably, the torso will move in the seat and the neck is stretched as the head remains fixed relative to the seat. Moreover, none of the prior art devices were intended for daily use by persons suffering neck dysfunction from trauma or disease.
U.S. Pat. No. 3,170,659 to Wood, Jr. describes a head restraint for use in a space vehicle that has a curved rear head support with ear flaps pivotally hinged to each side of the head support. The head support is mounted to a frame connected to a seat or an integral part of the space vehicle. A forehead strap and a chin strap connect between the ear flaps. This invention permits the head to slide inside the rigid back rest and side flaps while the chin and forehead straps pivot and follow the head. That way, when loads are applied to the vehicle causing the occupant to move in the seat, the occupant's neck is not stretched. This device is somewhat complicated and requires that the crewman be occupying a seat.
U.S. Pat. No. 3,397,688 to Gottfried describes a pneumatically inflated neck and head stabilizer. The stabilizer device attempts to achieve total immobilization of the head and neck through use of armpit straps as a means of attaching the device to the torso. The immobilizer consists of a helmet or hood for enveloping a patient's head. The helmet is fabricated of sheet material having inflatable pockets that contact the head while the armpit harness holds the helmet in place. This immobilizer device is obtrusive and does not relieve normal load forces placed on the neck as the neck supports the head.
U.S. Pat. No. 3,522,804 to Towbin describes an infant's neck and head support that is intended to prevent spinal injuries of the hyperextension or "whiplash" type, caused by sudden and extreme movement of the head. The support is made of molded rubber and extends over the child's shoulders, back and chest. A head support, shaped to conform to the child's head, extends upwards along the back of the infant's neck and head and is reinforced by stiffening ribs. This device controls only rearward head motions and was intended to be worn continuously during the first four months of life. This device does not use a tethering system to control head motion and does not help to relieve normal load forces placed on the neck as the neck supports the head. Also, this device tends to make it difficult for an infant to swallow.
U.S. Pat. No. 4,339,151 to Riggs describes a head restraint for supporting the head while a user is seated in a chair. The head restraint has a strap that is wrapped around the back of a chair and an adjustable headband secured to a central, forward portion of the strap. The headband is worn on the user's head for supporting the head. This device requires that the user be seated in the chair, is very noticeable and the device does not relieve normal load forces placed on the neck as the neck supports the head.
U.S. Pat. No. 4,451,932 to Wagemann et al describes a device intended for use in infants, especially premature infants. The device functions to produce total, temporary restraint of all limbs and the head during extensive medical procedures. The device is also classified as an article of chill reducing clothing.
U.S. Pat. No. 4,718,412 to Nesbitt describes a single use, emergency care cervical immobilization means comprised of a lightweight cervical spine board made of wax coated or plastic coated reinforced double walled corrugated board. The device has pre-cut score lines for folding the device around the sides of the head and around the sides of the body to substantially enclose the wearer's neck and throat. The device is primarily used to immobilize the human head, neck and torso for use in emergency situations to prevent further injury to a potentially injured cervical spine.
U.S. Pat. No. 4,903,711 to Gunther describes a device for preventing infant colic and stomach discomfort. The device has a vest that is worn by the infant during feeding and burping. A bubble level is attached to the vest for visually indicating the position of the infant's torso with respect to vertical. This is a cumbersome device that completely encircles the neck and that is required to be worn externally over the infant's clothing.
U.S. Pat. No. 4,638,510 to Hubbard describes a device intended for use by occupants and drivers of high performance vehicles to reduce motions or loading in the neck and the upper torso when the vehicle experiences sudden deceleration or acceleration. The device has a stiff yoke worn over the upper torso of the occupant and a high collar that extends upwards from the yoke, with a set of tethers connected between the lateral and rear portions of a helmet and the collar. The collar extends upwards to adjacent the center of gravity of the head and helmet which is at about eye level of the occupant. The tethers allow needed head movement and yet reduce the potential for fatigue and crash injury by carrying forces that would otherwise be transmitted through the neck, thus reducing extreme motions of the head.
Other patents describe restraining devices that are mounted to a seat of a high performance vehicle and clasp the head of the occupant to limit head motion relative to the seat. These include U.S. Pat. No. 3,376,064 to Jackson; U.S. Pat. No. 3,922,034 to Eggert; U.S. Pat. No. 4,477,041 to Dunne; U.S. Pat. No. 4,664,341 to Cummings; British Patent No. 656,079 to Bower and British Patent No. 978,422 to Fitzgerald and Fisher.
Other U.S. patents distantly related to the present invention include U.S. Pat. No. 3,099,261 to Doss et al; U.S. Pat. No. 4,508,294 to Lorch and U.S. Pat. No. 4,592,523 to Herndon.
What is needed is a device that can be worn by both ambulatory people and people confined to a chair and that regulates anterior, posterior and sidewards head motion and that further helps to partially relieve neck loads by coupling the head with the torso. That way, when the load carrying capacity of the neck is altered by muscle fatigue, disease or through traumatic damage to the cervical vertibrae, the person is still able to maintain an acceptable head position during daily activities.